Starbucks, the world’s largest chain of coffee shops, has introduced $1 reusable plastic cups at all of its stores in the U.S. and Canada, an initiative aimed at drastically reducing the company’s paper waste.

The coffee brand, which has more than 11,000 stores in the U.S. alone, tested the reusable cups at 600 stores this past October. Within just one month, they observed a 26% increase in reusable cup use from the same period a year earlier.

In 2011, 1.9% of drinks were sold in reusable cups in 2011, resulting in more than 1.5 million pounds of paper waste avoiding a landfill.

According to the company’s sustainability report, approximately four billion cups are used globally each year, the vast majority of which are disposable paper cups and are generally not recycled.

Even though their disposable cups are made of 10% recycled pulp, the billions of beverages served each year translate into deforestation and paper production, both of which are highly energy intensive processes. In addition, the paper cups have a wax-based lining on the inside that makes them difficulty to recycle.

Starbucks has not limited their sustainability efforts to reducing paper waste. The company has also made impressive gains in the past two years with front-of-store recycling, energy efficiency per store, renewable energy use, and decreased water consumption.